1. Field of the Invention
The present invention relates to a manufacture condition setting system which estimates a dynamic condition such as the set value of a manufacturing equipment, a manufacture condition setting method, a control program, and a computer-readable record medium recording a control program therein.
2. Description of the Related Art
For enhancing a product quality and a production efficiency, it is important to optimize dynamic conditions such as the set values of manufacturing equipments, from the beginning of the point of time of the alterations of static conditions such as a product model and a part characteristic.
Manufacture condition setting apparatuses in the prior art are as indicated below.
Patent Document 1 (Japanese Patent No. 3,195,637 registered on Jun. 1, 2001) discloses in an expert system for holding the empirical laws of manufacture conditions (material specifications, working conditions, etc.) and product specifications, a technique which selects materials suited to the product specifications, which determines the working conditions from the materials and the product specifications, and which adjusts and learns the working conditions in accordance with a small quantity of pre-production prototype or with the result of a sampling inspection.
Patent Document 2 (JP-A-2000-263110 laid open on Sep. 26, 2000) discloses in the continuous rolling control of a steel plate or the like, a technique which checks the degree of experience of a lot that is classified depending upon the kind of steel, the thickness of the plate, the width of the plate, etc., and which, when the degree of experience is low, amends a control method by using the learnt result of a lot of close sort as is highly experienced.
Patent Document 3 (JP-A-6-330164 laid open on Nov. 29, 1994) discloses in a hot-worked steel material, a technique which predicts the structure of a steel material after cooling, by using a transformation prediction model in accordance with components and heating/working conditions.
Patent Document 4 (JP-A-10-187206 laid open on Jul. 14, 1998) discloses a technique which holds the offset magnitudes between actual result values and values predicted from mathematical models (exponential smoothing) for respective product groups and respective treatment conditions, and which obtains common correction magnitudes as to temporal fluctuations.
However, the prior-art manufacture condition setting apparatuses as mentioned above have had problems as indicated below.
When the combinations of static conditions are large in number, it becomes difficult to acquire the knowledge items of dynamic conditions for all the combinations of static conditions, and hence, the number of man-hour for building a system and starting a service increases.
Knowledge once built in a system stores only the intensified results of past experiences. Therefore, even in a case where any of the past experiences is to be deleted on account of a drawback found later, the knowledge cannot be corrected.
Even if a dynamic condition for the inexperienced combination of static conditions is estimated by proportional allocations or from a prediction expression, the estimation is sometimes impossible in the existence of the static condition of a qualitative variable, because the sequence relation of the static condition is not uniquely determined.
When the combinations of static conditions are large in number, an enormous number of experiences are required for refining the knowledge items of dynamic conditions for all the combinations of static conditions, and hence, a term for enhancing the reliability of knowledge lengthens.
Even when the knowledge items of optimal dynamic conditions for all the combinations of static conditions have been completely acquired, the causal relations of qualities to the static conditions are not definite. Therefore, although the optimal dynamic conditions can be estimated, the optimal combination of static conditions cannot be searched for.